1. Technical Field
This invention relates generally to food processing equipment and, more particularly, to an improved net rucker for shirring netting onto a temporary carrier in the form of a net tube.
2. Discussion Of The Related Art
Tubular food stuffing netting is often used to hold together and package various types of meat products such as hams, loaves and the like. Typically, the netting is placed over an end of a stuffing horn and the meat products are forced into the netting through a chute in the stuffing horn. The netting is then removed from the horn and clipped around the stuffed meat product. Afterwards, the netted meat product is typically smoked or further processed as desired.
The food stuffing netting is available from a variety of manufacturers such as, without limitation, C&K Manufacturing and Sales Company of Bay Village, OH under the trademark ZIP-NET. The netting often comes in flattened rolls which require that the netting be unrolled and separated prior to use. Certain automated meat stuffing machines are designed for use with a tube that has a quantity of netting gathered or shirred onto it. This tube acts as a temporary carrier for the shirred netting. In operation, the meat stuffing machine forces the meat products into a closed end of the netting in a manner which feeds a portion of the netting from the tube. The meat product is surrounded by the netting which is then gathered and cut. A sufficient quantity of netting is shirred onto the tube so that several stuffing operations can be performed before having to replace the tube containing the shirred netting.
The present invention is primarily concerned with an improved apparatus and method in which the netting is shirre onto the tube. Currently, the aforementioned C&K Manufacturing and Sales Company sells what is known in the trade as a "net rucker" for shirring netting onto a net tube, shown generally in FIG. 1. The net rucker 10 employs a plurality of rigid spring loaded fingers 12 secured to a finger support bracket 14, shown more clearly in FIG. 2. In operation, the rigid spring loaded fingers 12 carry the netting 16 downwardly over a net tube 18 as the net tube 18 is reciprocated up and down on a movable platform 20. The net tube 18 includes a tube cap 22 fitted into the upper end of the net tube 18 to prevent the netting 16 from catching on the otherwise sharp ends of the net tube 18. An air cylinder 24 including a piston 26 connected to the movable platform 20 causes the net tube 18 to reciprocate up and down. During the downward stroke of the net tube 18, the rigid spring loaded fingers 12 slide over the crossbars 28 of the netting 16 until the movable platform 20 is extended to its lowermost position, as substantially shown in FIG. 1. During the upward stroke of the net tube 18, the rigid spring loaded fingers 12 engage the crossbars 28 of the netting 16 thereby causing the netting 16 to be pushed downward or shirred onto the net tube 18 as the movable platform 20 moves the net tube 18 upward.
In this manner, the net rucker 10 performs the operation of shirring the netting 16 onto the net tube 18. Unfortunately, the net rucker 10 has several drawbacks associated with its operation. One drawback of the net rucker 10 occurs while the net tube 18 is being reciprocated up and down. During this movement, the rigid spring loaded fingers 12 sometimes cut and/or rip the netting 16 as the rigid spring loaded fingers 12 pass over or engage the netting 16. This condition typically occurs because the spring loaded fingers 12 are rigid and have sharp pointed ends, as seen most clearly in FIGS. 1A and 2.
A second drawback of the net rucker 10 occurs while the net tube 18 is traveling upward, some of the rigid spring loaded fingers 12 may not fully engage the netting 16. This subsequently causes a portion of the netting 16 to slide past the non-engaged fingers 12, causing a non-uniform packing density of the shirred netting 16 on the net tube 18. This also results in less netting 16 being shirred onto the net tube 18, thus causing the net tube 18 to be replaced more often during the meat stuffing process. This further can cause the netting 16 to become entangled on the net tube 18 during the meat stuffing process.
A third drawback of the known net rucker 10 is that the rigid spring loaded fingers 12 can catch on the lip or seam between the net tube 18 and tube cap 22, as shown most clearly in FIG. 1A. As a result, damage to the net rucker or the netting can occur.
Another net rucker is disclosed in a commonly assigned U.S. Pat. No. 4,924,552 entitled "Net Rucker" issued May 15, 1990 to Michael J. Sullivan. Although these net ruckers meet their objective of shirring the netting 16 onto the net tube 18 there is still room for improvement of these devices. This invention is thus directed towards an improved net rucker which is capable of shirring food stuffing netting with a uniform packing density onto a net tube in an efficient and smooth running manner without degrading the condition of the netting.